Brush sign on susceptibility-weighted imaging as a predictor of infarct growth in a single small subcortical infarction.

Abstract

A single small subcortical infarction is sometimes strongly associated with infarct growth, ultimately leading to early neurological deterioration. We aimed to investigate whether a brush sign (BS) on susceptibility-weighted imaging (SWI) can predict infarct growth or progressive paralysis in a single small subcortical infarction. Consecutive patients with a single small subcortical infarction presenting within 24 h of onset were retrospectively evaluated. MRI, including SWI, was performed on admission and within 1 week of admission. Infarct growth was defined as an increase in infarct volume exceeding 0.5 cm³ between admission and follow-up on diffusion-weighted imaging. Progressive paralysis was defined as an increase in the manual muscle test score by > 1 point. Of the 67 patients (median age, 75 [62-83] years, 46 male) with a single small subcortical infarction, 13 (median age, 75 [59.5-84] years, 10 male) presented with a BS. The presence of a BS was associated with infarct growth; however, it was not an independent factor associated with progressive paralysis. On the other hand, infarct growth and age were independent factors associated with progressive paralysis. A BS could indicate infarct growth in cases of a single small subcortical infarction. Question The usefulness of MRI in predicting infarct growth in a single small subcortical infarction has not been reported sufficiently. Findings The presence of a brush sign on susceptibility-weighted imaging was independently associated with infarct growth in a single small subcortical infarction. Clinical relevance A brush sign on susceptibility-weighted imaging has important implications, as early identification of patients at high risk of infarct growth can guide tailored treatment strategies and monitoring to improve patient outcomes.